75835-25-5Relevant articles and documents
Palladium-Catalyzed Hiyama Coupling of Benzylic Ammonium Salts via C-N Bond Cleavage
Han, Chunyu,Zhang, Zhenming,Xu, Silin,Wang, Kai,Chen, Kaiting,Zhao, Junfeng
, p. 16308 - 16313 (2019/12/25)
The first palladium-catalyzed Hiyama cross-coupling of arylsilanes with benzyltrimethylammonium salts is reported. The reaction proceeds smoothly to facilitate C(sp2)-C(sp3) bond formation via cleavage of the C-N bond and provides a useful approach to various diarylmethanes with a broad substrate scope and excellent functional group tolerance in good to excellent yields.
A SO2F2 mediated mild, practical, and gram-scale dehydroxylative transforming primary alcohols to quaternary ammonium salts
Zhao, Chuang,Zha, Gao-Feng,Fang, Wan-Yin,Alharbi, Njud S.,Qin, Hua-Li
, p. 4648 - 4656 (2019/07/12)
A simple, practical and gram-scale process for direct transformation of primary alcohols or silyl ethers to ammonium salts was developed. This method has the feathers of easy work-up (a simple filtration), mild condition, high yield, great practicality and robustness. And the application of the ammonium salts in Suzuki coupling reaction was also accomplished.
Iridium-Catalyzed Borylation of Primary Benzylic C-H Bonds without a Directing Group: Scope, Mechanism, and Origins of Selectivity
Larsen, Matthew A.,Wilson, Conner V.,Hartwig, John F.
supporting information, p. 8633 - 8643 (2015/07/15)
Primary benzylic boronate esters are useful intermediates in organic synthesis, but these reagents cannot be prepared by hydroboration. The benzylic C-H borylation of methylarenes would be a method to form these products, but such reactions without neat methylarene or a directing group are unknown. We report an approach to divert the borylation of methylarenes from aromatic positions to benzylic positions with a silylborane as reagent and a new iridium catalyst containing an electron-deficient phenanthroline as ligand. This system forms benzylic boronate esters selectively over the corresponding aryl boronate esters. An Ir diboryl monosilyl complex ligated by the phenanthroline was isolated and determined to be the resting state of the catalyst. Mechanistic studies show that this complex is kinetically competent to be an intermediate in the catalytic process. Kinetic studies of benzylic and aryl C-H borylation catalyzed by various Ir complexes show that the rate of aryl C-H borylation decreases with decreasing electron density at the metal center of the Ir catalyst, but that the rate of benzylic C-H borylation is less sensitive to the degree of electron density at the metal center of the Ir catalyst. Kinetic and computational studies suggest that the two borylation reactions respond differently to the degree of electron density at the metal center because they occur with different turnover-limiting steps. The turnover-limiting step in the borylation of aryl C-H bonds is known to be C-H oxidative addition, but the turnover-limiting step of the borylation of benzylic C-H bonds appears to be an isomerization prior to C-B reductive elimination.
